Andy Murray is still to drop a set at the 2013 iteration of the Australian Open, but he was not happy with his performance during Saturday's third round victory over Ricardas Berankis.

The world No. 3 was given a severe examination by his part-time training partner, who created 12 break chances to Murray's 13 in a well-contested encounter. However, it was Murray who showed the greater clinical edge as he advanced 6-3 6-4 7-5.

It was the defence of Berankis that caused frustration for Murray, who consistently struggled to find a way past his rival. A modest tally of 24 winners in the match reflected the difficulty Murray encountered, with the Lithuanian smashing 37 of his own.

Midway through the second set Murray accused himself of playing "nonsense tennis", and there were further displays of anger as Berankis continued to change the pace of his shots throughout the match.

The first set could easily have gone to the underdog, who took one of eight break opportunities while Murray snatched both of his own.

Murray's serve was working well, delivering 13 aces in the contest, and the second set was arguably his best - despite the self-condemnation. He will want to improve his solidity behind the second serve, however, after dropping a host of points when his first delivery was off target.

It looked like a tiebreaker would be needed in the third set, but Murray broke with the score at 5-5 to book his spot in round four.

He will now face Gilles Simon for a place in the last-eight, after the Frenchman beat Gael Monfils 6-4 6-4 4-6 1-6 8-6. Simon appeared to suffer a fitness issue midway through the match but held on for a win that will have taken a lot out of him.